Packing of pulverulent materials and the like



Sept. 11,, 1962'? 1, w; 031 3,053,022

PACKING QF PULVERULENLT MKTERTALS' AND THE LIKE:

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INVEN TOR 1 Czfiezwes V0 2) ATTORNEYS PACKING OF PULVERULEN'B nmmmms' 1mm Filedi Jam. 2-4;, 1

Sept. 11 I, I962 INVENTOR Clarence "(V0 BY A,

Am ATTORNEY mm W, W 1

p 1962 c. w. VOGT 3,053,022

PACKING OF PULVERULENT MATERIALS AND THE! LIKE Filed Jan. 24, 1956 4 Sheets-Sheet 5 igs. 8 h 8/ 8% 6 I INVENTOR Clarence "(V0 15 Sept. 11, 1962 c. w. VOGT A 3,053,022

PACKING 0F PULVERULENT MATERIALS AND THE LIKE Filed Jan. 24, 1956 4 Sheets-Sheet 4 United States Patent ()flfice 3,053,022 Patented Sept. 11, 1962 3,t)53,22 PACKING F PULVERULEN'I MATERIALS AND THE LIKE Clarence W. Vegt, Rte. 4, Westport, Conn. Filed Jan. 24, 1956, Ser. No. 569,979 4 Claims. (Cl. 53-22) This invention relates to the art of packaging and more particularly to the method of packaging materials divided in small size particles and more specifically pulverulent materials and to the resulting individual packaged articles of such materials as well as to the equipment for forming such packages and the containers or wrappers thereof.

As conducive to an understanding of the invention, it is noted that in packaging for sale in grocery stores, such commodities as flour, pancake or cake mixes, of small particle size, generally pulverulent, when such commodities are sifted or poured into a receptacle such as a bag or container, the interstitial spaces between the particles and the head room resulting from the settling of the commodity after it is packed, results in an overall package size much larger than would normally be required if such interstitial spaces and head room were eliminated, with resultant need for greater shelf space and greater cost of packaging materials.

Furthermore, due to the adverse effect on certain materials, of the air with its entrained water vapor collected in such interstitial spaces and head room, wide variation may occur in the shelf life of packages of the same commodity thereby limiting the formulation of the materials that can thus be packaged.

It is accordingly among the objects of the invention to provide a relatively simple method for forming packages containing materials of the above type, in such manner that the finished package will be substantially devoid of interstitial spaces and head room and hence will contain a minimum amount of air and entrained water vapor and will be of minimum size for a given weight of material, thereby occupying a minimum of shelf pace, shipping bulk and wrapping material with resultant lowered cost of packaging, handling and storage.

Another object is to provide equipment for forming packages of the above type, which is relatively simple in construction, having but few parts which are not likely to become deranged and which may readily be operated to compact the material into its container.

Another object is to provide a container or wrapper which admits of ready charging with materials of the above type in desired compactness with a minimum of trapped air or interstitial spaces.

Another object is to provide a container or wrapper of the above type which facilitates opening thereof for removal of some or all of the contents thereof and subsequent rescaling.

In this connection, the invention utilizes a high pressure on the material in the magazine (and preferably a relatively low pressure in the container to be filled) which material is delivered into the container through a relatively small orifice thus producing a high velocity through such orifice and a rapid progressive release of interstitial air which is removed during the compacting action of the material in the container, when the pressure thereon is suddenly increased and its velocity decreased to zero. This is to be distinguished from packing operations where the material is compressed in a press.

More particularly, according to the present invention, a filling head is provided which may be positioned in sealing engagement with the mouth of the container to be charged, the head being provided with a hopper or magazine having an outlet in communication with the container. By means of a gas under pressure applied to the material in the hopper, a charge of such material will be forced into the container to fill the latter in compacted form and suitable vents are provided through which the air in the container may be discharged, such as by suction which may be applied prior to and during the filling of the container without loss of any of the material being forced into the container. The resultant package thus formed will have a minimum of interstitial spaces and a minimum of volume for a given weight.

The container or wrapper according to one embodiment of the invention may be a semi-rigid receptacle of cardboard, heavy paper, relatively stitf plastic or the like, which mounts a porous member, preferably opposed to the mouth thereof and having relatively fine openings, which substantially permit only the passage of gas therethrou-gh, the porous member in an illustrative embodiment of the invention being of uncoated paper such as commonly used for bread wrapping prior to wax coating.

According to another embodiment of the invention the container or wrapper may be or" flexible material having a porous portion which may be a window or the surface of the wrapper which substantially permits only the passage of gas therethrough.

This application is a continuation-in-part of my copending application Serial No. 556,158, filed December 27, 1955, now abandoned, and Serial No. 559,611, filed January 17, 1956, now abandoned.

In the accompanying drawings in which are shown one or more of various possible embodiments of the several features of the invention,

FIG. 1 is a top plan view of the bottom portion of the filing equipment in partially open position.

FIG. 2 is a view similar to FIG. 1 of the bottom portion of the filling equipment in closed position with the container in position,

FIG. 3 is a transverse sectional view taken along line 33 of FIG. 2,

FIG. 4 is a longitudinal sectional view taken along line 4-4 of FIG. 2,

FIG. 5 is a perspective view of the container in open position,

FIG. 6 is a longitudinal sectional view of the container in closed position, taken along line 66 of FIG. 7,

FIG. 7 is a transverse sectional View taken along line 7-'7 of FIG. 6,

FIG. 8 is a sectional view of a container according to another embodiment of the invention,

PEG. 9 is a fragmentary perspective view of a receptacle according to another embodiment of the invention,

FIG. 10* is a longitudinal sectional view of another embodiment of the filling equipment,

FIG. 11 is a transverse sectional view taken along line 11-11 of FIG. 10,

FIG. 12 is a detail view on an enlarged scale of the outlet of the filling head,

FIG. 13 is a perspective view of a package according to another embodiment of the invention,

FIG. 14 is a view similar to FIG. 9 of another embodiment,

FIGS. 15 and 16 are fragmentary detail views of still other embodiments, and

FIG. 17 is a perspective view of a preferred form of receptacle having a wavy edge to facilitate opening thereof.

Referring now to the drawings, in the illustrative embodiment shown in FIGS. 1 to 4 inclusive, the equipment for forming packages of the above type comprises a mold 11 having a bottom portion 12 and a head portion 13.

The bottom portion desirably has a pair of spaced 3 parallel side walls 14, and end walls 16, 17 which define a rectangular cavity C into which the container 20 to be filled may be positioned.

As shown in FIGS. 1 and 2, the bottom portion 12 may be constructed to define a plurality of cavities C and to this end, the bottom portion 12 has a floor 21 (FIGS. 3 and 4) and a pair of laterally movable side members 23 and 24 conformed to define the side and end walls 14, 16 and 15, 17 respectively. As is shown in FIG. 1, the members 23, 24 may be spaced from each other to permit the ready insertion of the containers 20 to be filled and when moved together to the position shown in FIG. 2, the rectangular cavities C will be formed so that the side and end walls 14, 15 and 16, 17 will support the corresponding surfaces of the container during the filling operation.

Each of the side and end walls 14, 15, 16 and 17 has a passageway 27 extending through its top surface 28 as at 29 and through its inner surface as at 30 and said passageways are connected by a line 3 1 to a junction 32.

The floor 2 1 of the mold as shown in FIGS. 3 and 4 has a plurality of recesses 33 each aligned with an associated cavity C formed by the side members 23 and 24 when they are in closed position. Each of the recesses 33, which illustratively is rectangular, desirably has a pcripheral shoulder 34 near the top thereof on which is seated a perforated plate 35 which is secured to the shoulder 34 as by screws 36 to retain the upper surface 37 of the plate 35 substantially flush with the corresponding surface of floor 21.

The floor 21 desirably has a. plurality of passageways 38 extending through the upper surface 37 thereof on each of the 'four sides of the associated recess 33 and a plurality of passageways 41 which lead into the recesses 33 as is shown in FIGS. 3 and 4. The passageways 38 and 41 are connected by lines 42 and 43 to junction 32.

As shown in FIG. 3, the junction 32 is connected by line 44 to the port 45 of a seelctor valve 46. The valve 46 has an outer casing 47 and an inner rotatable valve member 48 which in one position will connect port 45 to a port 51 which may be connected through a dust collector to a vacuum pump (not shown) and in a second position will connect a port 52 connected by line 53 to line 44, to a port 54 which leads to the atmosphere.

The head 13 of the mold 11 desirably comprises a substantially rectangular block 61 of length and width such that it may extend over the side members 23, 24 when they are in closed position. Affixed to the undersurf-ace of block 61 as by bonding is a sheet 62 of resilient material illustratively of rubber, of dimensions such that its end and side edges will cover the upper surfaces of the side and end walls 14, 15, 16, 17 of the mold when the latter is closed to effect a seal in the manner hereinafter described.

The block 61 illustratively has a plurality of pairs of recesses 63 therein, each pair being adapted to be aligned with an associated cavity C in the mold when the latter is closed. The recesses 63 are connected by passageways 6.4 in the block 61 and thence by line .65 to the port 66 of a selector valve 67 which in one position may connect the port 66 to a port 68 connected to a source of pressure and in a second position may connect the port 66 to a port 69 which desirably is connected through a dust collector (not shown) to a vacuum pump.

Positioned over each of the recesses 63 and secured to the block 61 is a perforated plate 71, having a screen 72 thereon having relatively fine openings therethrough, the sheet 62 of resilient material having openings 73 to accommodate the plates and screens as is shown in FIG. 3.

The block 61 desirably has a plurality of annular hubs 75 on its top surface which encompass an associated conical cavity 76 in said block, the apex of each of said cavities having an opening 77 aligned with a corresponding opening 78 in sheet 62 which is positioned over an associated cavity C in the bottom portion 12 when the mold is ready for filling.

Each of the hubs serves as the support for a magazine or hopper 7 9, illustratively a sleeve which may be charged in any suitable manner with the comminuted or pulverulent material with which the package is to filled and suitable means P are provided to apply a source of gas under pressure to the column of material in the magazines 79. If desired, a single reservoir containing the material to be packaged can be connected to the magazines or hoppers 79.

The head 13 is suitably mounted so that it may be moved vertically toward and away from the top of the bottom portion 12 to permit insertion into the bottom portion of the mold, of the containers to be filled.

A typical receptacle 20 for use with the equipment above described in the preparation of packages of moldable, comminuted, pulverulent or other nonform-retaining material such as flour, powdered cake mixes, crust mixes, or the like is shown in FIGS. 3, 5, 6 and 7.

Such receptacle 20 may comprise a rectangular container or box formed from cardboard, for example, and having end and side flaps 81, 82 and 83, 84 at its top or mouth and its bottom respectively, extending from its end walls 85 and side walls 86.

The container 211 when assembled for filling has its end flaps 83 folded inwardly as shown in FIG. 5, said flaps 83 preferably being short so as to define a relatively large gap or space 87 therebetween. Extending over the inwardly folded flaps 83 and bridging the space $7 is a porous member or filter 91 having relatively fine openings therethrough and which preferably is a rectangular sheet of porous paper of the type generally used for wrapping bread, but which is uncoated with wax or similar material.

As is clearly shown in FIG. 5, the filter 91 is of substantially the same length as the container 20 and is of greater width than the latter so as to extend beyond the side walls 36 thereof over the adjacent portions of flaps 84. Although the filter 91 may be affixed to the flaps 83, 34 in any suitable manner, it is desirably secured thereto as by gluing or heat sealing.

To fill the containers 20, the side members 23, 24 are moved apart as indicated in FIG. 1 and a container 21) with its bottom flaps 84 extending laterally outwardly is positioned in each of the spaces defined between side walls 1 4, 15 and end walls 16, 17 of the bottom portion 12. The side members 23, 24 are then moved together to define the cavities C and the containers will be retained in the respective cavities with the filters 91 positioned over the plates and with the side fiaps 84 retained between the floor 21 and the bottom surfaces of side walls 14, 15 as shown in FIG. 4.

With the top flaps 81, 82 folded over the top, the side and end walls 14, 15 and 16, 17 and with selector valve 46 in position to connect ports and 51 suction will be provided in lines 31, 42 and 43. The suction in line 31 will retain the flaps 81, 82 against the top surfaces of walls 14 to 17 and the side walls of the container against the inner surface of said walls 14 to 17 and the suction in line 42 will retain the bottom flaps 84 against the floor 21 of the mold.

The head 13 of the mold is then positioned directly over the bottom portion 12 and moved downwardly to the position shown in FIGS. 3 and 4 so that the portion of the resilient sheet 62 which covers the top surfaces of the side and end walls 14, 15, 16 and 17 will engage the out-folded flaps 82, 81 of the container 20 to provide a dependable seal.

With the selector valve 67 in position to connect ports 66 and 69, suction will be applied through line to recesses 63. As a result of such suction and the suction applied to recesses 33 through line 43, the air in the container will rapidly be evacuated or discharged therefrom.

Thereupon, with suction desirably maintained, gas under pressure is applied to the column of pulverulent material in each of the magazines 79 to force such material through the aligned openings 77, 78 into the respective containers. The gas is preferably dried before application to the column of material so that any gas that should enter the container will have a minimum of water vapor. As such air entrained with the material will be removed through screen 72 and filter 91. However, as the openings therein are sufficiently small to preclude the passage therethrough of any of the material being forced into the container, substantially none of such material will escape into the suction lines 43, 65. Consequently the container is jet filled at high velocity (the container being at least partially evacuated) from the material under pressure in the magazine.

In order to avoid the possibility of material being forced into the containers before the mold is completely closed, which might cause some of the pulverulent material to be blown into the filling room, suitable control means 90 are provided to prevent the application of gas under pressure to the material in the magazines 79 until after the vacuum in the container 20, due to the suction applied thereto, reaches a predetermined amount.

After the container is charged, the gas pressure on the charges of material in the magazines 79 may be released and the selector valve 46 is set to connect ports 52 and 54. Consequently, the pressure in suction lines 31, 42 and 43 and against fiaps 81, 82 and 84 and in recesses 33 will rise to atmospheric to permit ready removal of the container. The selector valve 67 may be set to connect ports 66 and 68 so that gas under pressure will be applied to line 65 and through perforated plates 71 to blow away from the screen 72 against the cornpacted material in the container, any material that may adhere thereto.

The head 13 is then moved away from the bottom portion 12 to permit removal of the charged container. As the portion of the charge of material remaining in magazines 79 will also be compacted due to the action of the gas pressure against the material. in the conical cavities 76, none of such material will fall through openings 78 during and after such movement of the head 13. If desired, the openings 78 may be provided with valves of suitable form (e.g., flap, cylinder, etc.) which may be manually or otherwise operated.

By reason of the filter 91 at the bottom of the charged containers against which the material forced into the container will compact, there will be no escape of such material through the filter when the containers are re moved from the mold. Thereupon the bottom and top flaps of the container may be sealed in conventional manner to close the container to complete the package.

The embodiment of the receptacle 20 shown in FIG. 8 is a cup-shaped container, illustratively a truncated cone. The mouth 101 of the container 20 desirably has a lip 102 to receive a conventional cover disc (not shown). The base of the container 20 has a screen 103 extending thereacross which may also be of porous paper such as is previously described.

The container 20 may be filled with pulverulent material by means similar to that shown in FIGS. 1 to 4, and after it is filled and removed from the molding equipment the undersurface of the screen 103 may be covered with wax or lacquer to fill up the pores in the screen or, if desired, a snap-in cover may be inserted onto the bottom of the container 20' so that when a cover disc is inserted into the mouth of the container 20' it will be completely closed for shipping.

The embodiment of the receptacle shown in FIG. 9 is formed from a wrapper of porous material such as a suitable paper which admits of molding the material in desired compactness into prismatic shape, illustratively a six sided package of rectangular or square cross section.

The Wrapper is similar to that shown in my copending application Serial No. 559,611, filed January 17, 1956, and comprises a sheet of porous flexible wrapping material having end edges, with a strip 105 of relatively stifi reinforcing material such as cardboard affixed to said sheet across the length thereof with the ends of said strip extending beyond the end edges of said sheet. The reinforcing strip 105 conforms to and is coextensive with one side and with the opposite ends of the package formed from such wrapper.

The wrapper in partially completed form prior to filling has one end sealed as at 106 and the side edges 107 of the wrapper, which extend beyond one edge of the package, are coated with a suitable adhesive 108 on their adjacent surfaces so that when secured together as shown, they form a fin seal 109 extending along the edge of the package.

The adhesive coating at the end 111 of the fin seal remote from the sealed end of the partially completed package, tapers outwardly as at 112 so that it is narrower at such end 111 than along the length of the fin seal to permit expansion of thet open end or month 113 of the wrapper to facilitate insertion of a filling nozzle in the manner to be described. The wrapper has now become an open mouth bag but will be referred to as a wrapper.

To fill the partially completed wrapper shown in FIG. 9, equipment of the type shown in FIGS. 10 and 11 may be provided. The filling equipment comprises a mold 115 having a bottom portion 116 and a head portion 117.

The bottom portion 116 has a floor 113' and a pair of laterally movable side members 119 and 121 conformed to define opposed pairs of side walls 122, 123 and 124, 125 respectively. The members 119, 121 may be spaced from each other to permit the ready insertion of the wrapper to be filled and when moved together to the position shown in FIG. 11 will define a rectangular cavity C.

Means are provided to withdraw gas from the wrapper in the mold prior and during the filling operation. To this end the inner surface of each of the side walls of the mold is provided with a multiplicity of relatively small openings 128 which are in communication at their inner ends with a passageway 129 to which suction may be applied by a suitable vacuum pump (not shown).

The head 117 of the mold which is suitably mounted so that it may be moved vertically into the cavity C desirably comprises a rectangular block 131 that is substantially rectangular in cross section, of dimensions slightly less than the corresponding dimensions of the cavity C in the mold so that it may fit thereinto.

The block desirably has a substantially conical cavity 132 therein, the apex of which has an outlet opening 133 aligned with the cavity C in the mold when the mold is ready for filling. The cavity 132 may be charged in any suitable manner with the comminuted or pulverulent material with which the wrapper is to be filled and suitable means are provided to apply a source of gas under pressure to the column of material in the magazine or cavity 132.

To prevent escape of material from the cavity 132 in the block 131 when suction is applied to passageways 129, valve means are provided for outlet opening 133. To this end, a plate 135 is aflixed as by screws 136 to the undersurface of block 131 so that an opening 137 in the plate 135 is aligned with outlet opening 133. A valve plate 138 is pivoted as at 139- to plate 135 and normally retained in sealing position with respect to opening 137 by a spring 141. In the drawings the valve is illustrated as having only one plate. Obviously it may be formed of two shorter plates meeting in the median plane of the opening, or in fact, the valve could be cylindrical, disc or of other form, thus not disturbing material that has been filled into the bag through the opening.

To provide a seal when the block is positioned in the mouth of the wrapper to be filled, a resilient gasket 142 is mounted on the undersurface of block 131 extending 9, the side members 119 and 121 of the mold are moved apart and the wrapper is positioned in the cavity C with the closed end 106 of the wrapper against the floor 11S and with the fin seal 109' between the edges 143, 144 of members 119 and 121. With the wrapper thus positioned, the portions 145 thereof adjacent its mouth 113 will extend upwardly beyond the top of the cavity C in the mold. The members 119, 121 are then moved partially together, and thereupon the block 131 may be moved into the open mouth 113 of the Wrapper. By reason of the tapered end 112 of the fin seal 109, the mouth of the wrapper will expand to permit ready insertion of the block 131. When the block is thus positioned in the wrapper, the side mem bers 119, 121 are moved to fully closed position. As a result, the side walls of the wrapper adjacent its mouth will be compressed between the side walls of the mold and the resilient gasket 142 to provide a seal with respect to the filling head and the fin seal 109 will be securely gripped between the juxtaposed edges 143, 144.

Thereupon, suction may be applied to the passageway 129 in the bottom portion 116. By reason of the porosity of the wrapper material, the gas in the wrapper will readily be evacuated therefrom, the spring urged valve plate 138 retaining the opening 133 of cavity 132 in closed condition to prevent escape of the material in the cavity during initial evacuation of the gas from the wrapper.

Thereupon, with the suction maintained, the source of gas under perssure may be applied to the column of material in cavity 132 to spray such material through aligned openings 133, 137 and past the valve plate 138 into the wrapper. As such material enters the wrapper due to the suction in passageways 129, interstitial air entrained with the material will be released by the compac tion of solid particles caused by sudden increase in pressure on each particle as its high velocity is suddenly arrested, and such released air will be removed through the porous wall of the wrapper. However, as the openings in the pores in the wrapper are sufiiciently small to preclude the passage therethrough of any of the material being forced into the wrapper, substantially none of such material will escape. Consequently, the wrapper will quickly fill and the material therein will be highly compacted so that the interstitial spaces therein will be reduced to a minimum.

After the wrapper is filled, the gas under pressure is released as is the suction to passageways 129 and the head portion 117 moved up to clear flaps 145. During the first portion of such movement, the plate 138 will close, preventing material from falling through openings 133, while the top of the bag is closed and sealed and during its removal and replacement with another empty unit as herein before described.

To facilitate removal of the contents of the package, the opposed surfaces 151, 152 (FIG. 13) defining the fin seal 109 may have self-stick adhesive thereon which though affording a complete seal will permit ready separation of the opposed surf-aces. Thus, if the housewife wishes to remove a small quantity of the material, she need merely separate the opposed surfaces 151, 152 and insert a spoon through the resultant opening to remove the desired quantity of material. Thereafter, the surfaces 151, 152 may be pressed together to close the mouth of the package.

If desired, instead of retaining the partially completed Wrapper in the mold by the clamping of the fin seal 109 between edge 143, 144 of side members 119, 121, the wrapper in partially completed form, as shown in FIG. 14, may have the fin seal 109 resting against the top of the wrapper and the end 106' of the Wrapper which is securely sealed may have portions thereof extending laterally outward to define fins 153.

In such case, the portion 116 of the mold may have the bottom surface of its side members 119, 121 conformed with recesses (not shown) in which the fins 153 will :be

securely retained when the side members are in closed position.

In the embodiments shown in FIGS. 15 and 16, the wrappers may be identical to those shown in FIGS. 9 and 14 but of non-porous material such as polyethylene. The wrapper shown in FIG. 15 has a window or opening provided in the surface thereof opposed to the reinforcing strip and a sheet 161 of porous material extends over said opening 160 on the interior of the wrapper so that the gas in the wrapper may be evacuated through such sheet 161. After the package formed from the wrapper shown in FIG. 15 is filled and sealed, a label or similar cover (not shown) of non-porous material may be secured to the wrapper over the porous sheet 161 to completely seal the package.

In the embodiment shown in FIG. 16, the wrapper which also is of non-porous material has a window 162 in the surface thereof opposed to the reinforcing strip and a sheet 163 of porous material also extends over said opening on the interior of the wrapper. The portion of the wrapper material defined by the window 162 forms a flap 164 which is sealed over the sheet of porous material after the wrapper is filled to completely seal the package.

In the form of the invention shown in FIG. 17, the edges of the wrapper forming the container are formed with wavy or undulating profiles, offset as shown, to facilitate the opening of the container or wrapper. For example, the fin is formed by the inner extremity or flap 171 and the outer extremity 172. When this material is cut from a continuous band of material, the flaps on one extremity will mate with the hollows on the other extremity of one wrapper. In this fashion, flaps 173 will overlie hollows 174 to permit adjacent flaps on the extremities 17-1 and 172 to be grasped to facilitate the opening of the container.

In packaging the container in multiple units, the fins of adjacent units of a pair are adhered to the surfaces of adjacent units on opposite sides of the pair by placing the units face to face with the fins extending in opposite directions. In this fashion, adhesive material on the flaps 173 can be adhered to the underlying surfaces of the adjacent unit and the units of a pair are thus efiectively secured together.

At least a portion of the material of the container is preferably made of infusion or filter paper now commonly used, for example, in tea bags and the like. These papers may carry on at least a portion of their surface thermoplastic fibres or coatings to facilitate heat sealing thereof while at the same time permitting a high rate of passage of air therethrough. For example, in one form of such papers using only one ounce differential pressure, the paper passes 93 cubic inches per second per square inch of effective filter area. At this rate, a container of 9 cubic inches capacity can be effectively evacuated in a small fraction of a second through an area of paper of only 1 square inch.

By reason of the compacting of the nonform-retaining material, a given weight of material will occupy a considerably smaller volume than a corresponding non-com,- pacted weight of the same material. Thus, for certain pulverulent materials compacted at a pressure of 100 psi, for example, the volume of the package may be approximately sixty percent of the volume of an equivalent weight of non-compacted material. Consequently, the amount of shelf space to store and display the packages is greatly reduced as is the quantity of material to form the container.

In addition, as interstitial spaces are reduced to a minimum and as there is substantially no head space, there will be little air with its entrained water vapor in the completed package which gives increased flexibility in the type and formulation of materials that can be packaged.

As many changes could be made in the above method, equipment and articles, and many apparently widely different embodiments of this invention could be made without departing from the scope of the claims, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. The method of packaging small particles of material which comprises positioning a container having an open mouth and an end through which gas can flow adjacent to a source of material to be packed, eifecting a seal between said source and said mouth, applying suction to the mouth and to said end of said container to Withdraw gas therefrom, applying a gas under pressure several times greater than atmospheric against the material to force such material into the container while simultaneously withdrawing gas from said container and restraining escape of the material forced into the container, thereby to compact such material into the container, interrupting the discharge of material after the container is charged and sealing said end and said mouth.

2. Equipment of the character described comprising a mold having a bottom portion and a head portion, said bottom portion comprising a floor, a pair of parallel side walls and a pair of parallel end walls defining a cavity therebetween, said head portion comprising a member of dimensions greater than that of said cavity and having a resilient sealing member on its undersurface to engage the upper edges of said side and end walls, a hopper carried by said head portion to receive a charge of small particle material, said hopper having a restricted outlet at its lower end to provide communication into said cavity, and means for applying a source of gas under pressure several times greater than atmospheric to the contents of said hopper to force such contents through said outlet, said floor having a recess therein, a perforated plate extending over said recess and having its upper surface substantially flush with said floor, a passage leading from said recess to the exterior 10 of said bottom portion and means for applying suction to the passageway in said bottom portion.

3. The combination set forth in claim 2 in which said bottom portion has a pair of side members each defining a side and end wall of said two pairs of Walls, said side members being movable laterally toward and away from each other with respect to the floor of said bottom portion.

4. Equipment for filling a container with pulverulent material comprising a mold having a bottom portion and a head portion, said bottom portion comprising a floor, a pair of parallel side walls and a pair of parallel end walls defining acavity therebetween to receive such container, said head portion comprising a member of dimensions greater than that of said cavity and having a resilient sealing member on its undersurface to cover the top surface of said side and end walls, a hopper carried by said head portion to receive a charge of material, said hopper having an outlet at its lower end to provide communication into said cavity, said head having a recess in its undersurface to be aligned with said cavity, a screen over said recess to restrain passage of material therethrough, said head having a passageway from said recess to the exterior thereof, suction means connected to said passageway to create a vacuum in the container in said recess to withdraw gas therefrom and means operative when such vacuum has reached a predetermined value to apply a source of gas under pressure several times greater than atmospheric to the contents of said hopper to force such contents through said outlet into such container.

References Cited in the file of this patent UNITED STATES PATENTS 524,649 Becker Aug. 14, 1894 2,328,798 Gardner Sept. 7, 1943 2,564,969 Goldberg Aug. 21, 1951 2,663,128 Stirn et al. Dec. 22, 1953 2,775,084 Stirn et a1 Dec. 25, 1956 2,815,621 Carter Dec. 10, 1957 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,053,022 September 11, 1962 Clarence W, Vogt It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 1, line 40, for "pace" read space =5 column 2, line 34, for "filing" read filling column 3, line 37, for "see'lctor" read selector column 4, line 4, after to insert be column 6, line 19, for thet read =--n the column 10, list of references cited, add the following:

2,337,695 Valentine et al Dec, 28, 1943 2,538,441 Carter Jano 16, 1951 2,611,938 Hansberg Sept,, 30, 1952 2,741,009 Slayter et a1 Apr, 10, 1956 2,780,247 Claassen et al Feb, 5, 1957 2,475,323 James July 5, 1949 2,527,685 Roush Oct, 31, 1950 2,257,433 'Stokes Sept, 30, 1941 2,606,412 Salfisberg we Augo 12, 1952 Signed and sealed this 20th day of November 1962o (SEAL) Attest:

ERNEST W, SWIDER DAVID L, LADD Attesting Officer 9 Commissioner of Patents 

